Dye, filler made therefrom, compositions including the filler, and method of determining degree of cure of such compositions

ABSTRACT

A compound represented by formula: 
                         
and a treated filler having the compound on at least a portion of its surface. R is hydrogen or alkyl. X is alkylene, arylalkylene, or alkylarylene, each optionally interrupted by at least one of an ether, thioether, amine, amide, ester, thioester, carbonate, thiocarbonate, carbamate, thiocarbamate, urea, or thiourea, with alkylene optionally interrupted by arylene. W is hydroxyl, a sulfonic acid group, a phosphonic acid group, carboxylic acid group, —NHR 1 , epoxy, or —Si(Y) x (Z) 3-x . Y is alkyl, aryl, arylalkylenyl, or alkylarylenyl. Z is halide, hydroxyl, alkoxy, aryloxy, acyloxy, polyalkyleneoxy, —O— covalently bonded to the surface of the filler, or —O bonded to another silicon atom, and x is 0 or 1. A composition including the treated filler, a method of making the treated filler, and a method of determining the degree of cure of a curable polymeric resin are also disclosed.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a continuation of U.S. application Ser. No.15/109,350, filed Jun. 30, 2016, now U.S. Pat. No. 10,233,307, which isa national stage filing under 35 U.S.C. 371 of PCT/US2014/071683, filedDec. 19, 2014, which claims priority to U.S. Provisional Application No.61/921,644, filed Dec. 30, 2013, the disclosures of which areincorporated by reference in their entirety herein.

BACKGROUND

Inclusion of a dye in a curative or catalyst composition can be useful,for example, when the curative or catalyst must be admixed with acurable resin before placement and curing the resin. The dye can beuseful, for example, for indicating that the curative or catalyst isuniformly mixed with the curable resin. Peroxide and dye formulations inwhich the color disappears when the peroxide is used to generateradicals during the cure of a curable resin are also known. See, forexample, Japanese Pat. Appl. Kokai No. SHO 59-120612, published Jul. 21,1984, and U.S. Pat. Appl. Pub. No. 2006/0202158 (Chen et al.). Althoughthere are many ways to determine the extent of cure in cured systems,most methods require sampling and subsequent analysis of that sampleusing any of a number of techniques (e.g., spectroscopy, chromatography,and rheological measurements). These methods require equipment and mayrequire interruption of a process since many of these methods cannot beperformed while a manufacturing process is taking place. In addition,many of the analysis methods require a skilled user capable ofinterpreting results. Formulations including a dye and a catalyst orcurative in which the color disappears upon curing provide a visualindication of cure, which does not require equipment or extensiveinterpretation.

SUMMARY

The present disclosure provides a dye compound that can be bonded onto afiller particle. The filler can then be incorporated, for example, intoa composition that cures by free-radical initiated additionpolymerization. The bonding of the dye compound onto the fillereliminates the potential for dye components to bloom or leech out of thecured system. Although for some compounds, modification of the dyestructure can greatly alter the dye properties, we have found for thecompounds disclosed herein that modification of the dye compound andbonding it to a filler can be carried out without destroying the abilityof the dye to become colorless upon curing a curable composition.

In one aspect, the present disclosure provides treated filler. Thetreated filler includes a filler having on at least a portion of itssurface a compound of formula

The compound is at least one of covalently bonded, ionically bonded, orhydrogen-bonded to the filler. In this compound R is hydrogen or alkyl;X is alkylene, arylalkylene, or alkylarylene, wherein alkylene,arylalkylene, and alkylarylene are optionally interrupted by at leastone of an ether, thioether, amine, amide, ester, thioester, carbonate,thiocarbonate, carbamate, thiocarbamate, urea, or thiourea, and whereinalkylene is optionally interrupted by arylene; W is hydroxyl, a sulfonicacid group, a phosphonic acid group, carboxylic acid group, —NHR¹,epoxy, or —Si(Y)_(x)(Z¹)_(3-x); R¹ is hydrogen, alkyl, aryl,arylalkylenyl, or alkylarylenyl; Y is alkyl, aryl, arylalkylenyl, oralkylarylenyl; each Z¹ is independently halide, hydroxyl, alkoxy,aryloxy, acyloxy, polyalkyleneoxy, —O— covalently bonded to the surfaceof the filler, or —O— bonded to another silicon atom (e.g., on anothermolecule of the compound) to form a siloxane, wherein alkoxy and acyloxyare optionally substituted by halogen, and wherein aryloxy is optionallysubstituted by halogen, alkyl, or haloalkyl; and x is 0 or 1. In someembodiments, the filler is a siliceous filler. In some of theseembodiments, W is —Si(Y)_(x)(Z¹)_(3-x), and at least one Z¹ is —O bondedto another silicon atom on a surface of the filler forming a siloxanebond with the surface.

In another aspect, the present disclosure provides a compositionincluding a curable polymeric resin and the treated filler according toany of the foregoing embodiments.

In another aspect, the present disclosure provides a method fordetermining degree of cure of a curable polymeric resin. The methodincludes providing a composition comprising a curable polymeric resin, afree-radical initiator, and the treated filler in an amount sufficientto provide the composition with a first absorbance at a wavelength in arange from 400 nanometers to 700 nanometers and allowing the compositionto cure to provide a cured composition, wherein the cured compositionhas a second absorbance at the wavelength that is different from thefirst absorbance.

In another aspect, the present disclosure provides a method of making atreated filler. The method includes treating a filler with a compoundrepresented by formula:

In this formula, R is hydrogen or alkyl; X is alkylene, arylalkylene, oralkylarylene, wherein alkylene, arylalkylene, and alkylarylene areoptionally interrupted by at least one of an ether, thioether, amine,amide, ester, thioester, carbonate, thiocarbonate, carbamate,thiocarbamate, urea, or thiourea, and wherein alkylene is optionallyinterrupted by arylene; W is hydroxyl, a sulfonic acid group, aphosphonic acid group, carboxylic acid group, —NHR¹, epoxy, or—Si(Y)_(x)(Z¹)_(3-x); R¹ is hydrogen, alkyl, aryl, arylalkylenyl, oralkylarylenyl; Y is alkyl, aryl, arylalkylenyl, or alkylarylenyl; Z¹ ishalide, hydroxyl, alkoxy, aryloxy, acyloxy, polyalkyleneoxy, —Ocovalently bonded to a surface of the filler, or —O— bonded to anothersilicon atom to form a siloxane; wherein alkoxy and acyloxy areoptionally substituted by halogen, and wherein aryloxy is optionallysubstituted by halogen, alkyl, or haloalkyl; and x is 0 or 1.

In another aspect, the present disclosure provides a compoundrepresented by formula:

In this formula, R is hydrogen or alkyl; X is alkylene, arylalkylene, oralkylarylene, wherein alkylene, arylalkylene, and alkylarylene areoptionally interrupted by at least one of an ether, thioether, amine,amide, ester, thioester, carbonate, thiocarbonate, carbamate,thiocarbamate, urea, or thiourea, and wherein alkylene is optionallyinterrupted by arylene; W is hydroxyl, a sulfonic acid group, aphosphonic acid group, carboxylic acid group, —NHR¹, epoxy, or—Si(Y)_(x)(Z)_(3-x); R¹ is hydrogen, alkyl, aryl, arylalkylenyl, oralkylarylenyl; Y is alkyl, aryl, arylalkylenyl, or alkylarylenyl; Z ishalide, hydroxyl, alkoxy, aryloxy, acyloxy, polyalkyleneoxy, or —Obonded to another silicon atom to form a siloxane, wherein alkoxy andacyloxy are optionally substituted by halogen, and wherein aryloxy isoptionally substituted by halogen, alkyl, or haloalkyl; and x is 0 or 1,with the proviso that when X is ethylene, W is other than hydroxyl.

In this application:

Terms such as “a”, “an” and “the” are not intended to refer to only asingular entity, but include the general class of which a specificexample may be used for illustration. The terms “a”, “an”, and “the” areused interchangeably with the term “at least one”.

The phrase “comprises at least one of” followed by a list refers tocomprising any one of the items in the list and any combination of twoor more items in the list. The phrase “at least one of” followed by alist refers to any one of the items in the list or any combination oftwo or more items in the list.

The terms “cure” and “curable” refer to joining polymer chains togetherby covalent chemical bonds, usually via crosslinking molecules orgroups, to form a network polymer. Therefore, in this disclosure theterms “cured” and “crosslinked” may be used interchangeably. A cured orcrosslinked polymer is generally characterized by insolubility, but maybe swellable in the presence of an appropriate solvent.

The term “polymer or polymeric” will be understood to include polymers,copolymers (e.g., polymers formed using two or more different monomers),oligomers or monomers that can form polymers, and combinations thereof,as well as polymers, oligomers, monomers, or copolymers that can beblended.

“Alkyl group” and the prefix “alk-” are inclusive of both straight chainand branched chain groups and of cyclic groups. In some embodiments,alkyl groups have up to 30 carbons (in some embodiments, up to 20, 15,12, 10, 8, 7, 6, or 5 carbons) unless otherwise specified. Cyclic groupscan be monocyclic or polycyclic and, in some embodiments, have from 3 to10 ring carbon atoms.

“Alkylene” is the multivalent (e.g., divalent or trivalent) form of the“alkyl” groups defined above.

“Arylalkylene” refers to an “alkylene” moiety to which an aryl group isattached.

“Alkylarylene” refers to an “arylene” moiety to which an alkyl group isattached.

The term “aryl” as used herein includes carbocyclic aromatic rings orring systems, for example, having 1, 2, or 3 rings and optionallycontaining at least one heteroatom (e.g., O, S, or N) in the ring andoptionally substituted by up to five substituents including one or morealkyl groups having up to 4 carbon atoms (e.g., methyl or ethyl), alkoxyhaving up to 4 carbon atoms, halo (i.e., fluoro, chloro, bromo or iodo),hydroxy, or nitro groups. Examples of aryl groups include phenyl,naphthyl, biphenyl, fluorenyl as well as furyl, thienyl, pyridyl,quinolinyl, isoquinolinyl, indolyl, isoindolyl, triazolyl, pyrrolyl,tetrazolyl, imidazolyl, pyrazolyl, oxazolyl, and thiazolyl.

“Substituted styrene” includes alkyl, alkenyl, alkoxy, andhalogen-substituted styrene.

The term “size” is considered to be equivalent with the diameter andheight, for example, of glass bubbles.

All numerical ranges are inclusive of their endpoints and non-integralvalues between the endpoints unless otherwise stated (e.g., 1 to 5includes 1, 1.5, 2, 2.75, 3, 3.80, 4, 5, etc.).

DETAILED DESCRIPTION

In some embodiments, the dye is represented by formula:

In formula I, R is hydrogen or alkyl. In some embodiments, R is hydrogenor alkyl having 1 to 4 carbon atoms (e.g., methyl, ethyl, n-propyl,isopropyl, n-butyl, isobutyl, or sec-butyl). In some embodiments, R ishydrogen.

In formula I, X is alkylene, arylalkylene, or alkylarylene, whereinalkylene, arylalkylene, and alkylarylene are optionally interrupted byat least one of an ether (i.e., —O—), thioether (i.e., —S—), amine(i.e., —NR¹—), amide (i.e., —N(R¹)—C(O)— or —C(O)—N(R¹)—), ester (i.e.,—O—C(O)— or —C(O)—O—), thioester (i.e., —S—C(O)—0 or —C(O)—S—),carbonate (i.e., —O—C(O)—O—), thiocarbonate (i.e., —S—C(O)—O— or—O—C(O)—S—), carbamate (i.e., —(R¹)N—C(O)—O— or —O—C(O)—N(R¹)—,thiocarbamate (i.e., —N(R¹)—C(O)—S— or —S—C(O)—N(R¹)—, urea (i.e.,—(R¹)N—C(O)—N(R¹)—), or thiourea (i.e., —(R¹)N—C(S)—N(R¹)—), and whereinalkylene is optionally interrupted by arylene. In any of these groupsthat include an R¹, R¹ is hydrogen, alkyl, aryl, arylalkylenyl, oralkylarylenyl. In some embodiments, R¹ is hydrogen or alkyl, forexample, having 1 to 4 carbon atoms (e.g., methyl, ethyl, n-propyl,isopropyl, n-butyl, isobutyl, or sec-butyl). In some embodiments, R¹ ismethyl or hydrogen. The phrase “interrupted by at least one functionalgroup” refers to having part of the alkylene, arylalkylene, oralkylarylene group on either side of the functional group. An example ofan alkylene interrupted by an ether is —CH₂—CH₂—O—CH₂—CH₂—. Similarly,an alkylene that is interrupted by arylene has part of the alkylene oneither side of the arylene (e.g., —CH₂—CH₂—C₆H₄—CH₂—). In someembodiments, including any of the embodiments of R defined above, X isalkylene that is optionally interrupted by at least one ether, ester,carbonate, carbamate, or arylene. In some embodiments, X is alkylenethat is interrupted by —O—C(O)—NH— and optionally interrupted by —O—. Inthese embodiments, X may be, for example,—CH₂—CH₂—O—C(O)—N(H)—CH₂—CH₂—CH₂—. In some embodiments, X is alkyleneinterrupted by —O— and arylene.

In formula I, W is hydroxyl (e.g., —OH), a sulfonic acid group (i.e.,—SO₃M), a phosphonic acid group (i.e., —PO₃M), carboxylic acid group(—CO₂M), amino (—NHR¹), epoxy, or silane (—Si(Y)_(x)(Z)_(3-x)) or(—Si(Y)_(x)(Z¹)_(3-x)). In —NHR¹, R¹ can have any of the definitionsdescribed above. In some embodiments, including embodiments of thecompound not on the surface of the filler, the treated filler, and themethod of making the treated filler, W is a sulfonic acid group (i.e.,—SO₃M), a phosphonic acid group (i.e., —PO₃M), carboxylic acid group(—CO₂M), epoxy, or silane (—Si(Y)_(x)(Z)_(3-x),) or(—Si(Y)_(x)(Z¹)_(3-x)). In some embodiments, W is a sulfonic acid group(i.e., —SO₃M), a phosphonic acid group (i.e., —PO₃M), carboxylic acidgroup (—CO₂M), or a silane (—Si(Y)_(x)(Z)_(3-x)) or(—Si(Y)_(x)(Z¹)_(3-x)). In some embodiments, W is carboxy (—CO₂M), or asilane (—Si(Y)_(x)(Z)_(3-x)) or (—Si(Y)_(x)(Z¹)_(3-x)). In someembodiments, W is a silane. In some embodiments of the compound offormula I, including embodiments of the compound not on the surface ofthe filler, the treated filler, and the method of making the treatedfiller, when X is ethylene, W is other than hydroxyl.

For any of the embodiments in which W is an acid group (e.g., acarboxylic acid, sulfonic acid, or phosphonic acid), M is hydrogen, afree anion, or a counter cation. Examples of useful counter cationsinclude alkali metal ions (e.g., sodium, potassium, and lithium),alkaline earth metal ions (e.g., calcium and magnesium), ammonium, andalkyl ammonium (e.g., dialkylammonium, trialkylammonium, andtetraalkylammonium wherein alkyl is optionally substituted by hydroxyl,fluoride, or aryl). Compounds of formula I in which W is an acid groupcan be prepared as acids, in which M is hydrogen, or salts in which M isa counter cation. Free anions on the acid group are possible, forexample, when the compound of formula I has an ionic interaction withthe surface of a filler, as described in further detail below.

For any of the embodiments in which W is a silane (—Si(Y)_(x)(Z)_(3-x))or (—Si(Y)_(x)(Z¹)_(3-x)), Y is a non-hydrolyzable group. Y is selectedfrom the group consisting of alkyl, aryl, arylalkylenyl, andalkylarylenyl. In some embodiments, including any of the embodiments ofX and R as defined above, Y is alkyl or arylalkylenyl. In some of theseembodiments, Y is alkyl (e.g., methyl or ethyl).

For any of the embodiments in which W is a silane (—Si(Y)_(x)(Z)_(3-x)or (—Si(Y)_(x)(Z¹)_(3-x)) each Z or Z¹ can independently be a halide(i.e., fluoride, chloride, bromide, or iodine), hydroxyl (i.e., —OH),alkoxy (e.g., —O-alkyl), aryloxy (e.g., —O-aryl), acyloxy (e.g.,—O—C(O)-alkyl), or polyalkyleneoxy (e.g.,-[EO]_(h)-[R′O]_(i)-[EO]_(h)-R″ or -[R′O]_(i)-[EO]_(h)-[R′O]_(i)-R″,wherein EO represents —CH₂CH₂O—; each R′O independently represents—CH(CH₃)CH₂O—, —CH₂CH(CH₃)O—, —CH(CH₂CH₃)CH₂O—, —CH₂CH(CH₂CH₃)O—, or—CH₂C(CH₃)₂O— (in some embodiments, —CH(CH₃)CH₂O— or —CH₂CH(CH₃)O—),each h is independently a number from 1 to 150 (in some embodiments,from 7 to about 150, 14 to about 125, 5 to 15, or 9 to 13); and each iis independently a number from 0 to 55 (in some embodiments, from about21 to about 54, 15 to 25, 9 to about 25, or 19 to 23); and wherein R″ ishydrogen or alkyl having up to four carbon atoms). Alkoxy and acyloxyare optionally substituted by halogen, and aryloxy is optionallysubstituted by halogen, alkyl (e.g., having up to 4 carbon atoms), orhaloalkyl. In some embodiments, alkoxy and acyloxy have up to 6 (or upto 4) carbon atoms. In some embodiments, aryloxy has 6 to 12 (or 6 to10) carbon atoms. In some embodiments, including any of the embodimentsof X, R, and Y defined above, each Z or Z¹ is independently selectedfrom the group consisting of halide, hydroxyl, alkoxy, aryloxy, andacyloxy. In some embodiments, each Z or Z¹ is independently selectedfrom the group consisting of halide (e.g., chloride) and alkoxy havingup to ten carbon atoms. In some of these embodiments, each Z or Z¹ isindependently alkoxy having from 1 to 6 (e.g., 1 to 4) carbon atoms. Insome of these embodiments, each Z or Z¹ is independently methoxy orethoxy. In some embodiments, including any of the embodiments of X, R,and Y defined above, each Z or Z¹ is independently methoxy, acetoxy,phenoxy, bromo, or chloro. In some of these embodiments, each Z or Z¹ isindependently methoxy, acetoxy, or chloro.

In some embodiments of the treated filler or method of making a treatedfiller according to the present disclosure, Z¹ can also be —O—covalently bonded to the surface of the filler or —O— bonded to anothersilicon atom to form a siloxane. For example, in a reaction medium thatincludes water, hydrolysis of hydrolyzable Z¹ groups (e.g., alkoxy,acyloxy, poly(alkyleneoxy), or halo) of reactive silanes typicallygenerates silanol groups, which participate in condensation reactions toform siloxanes, which may be dimers, trimers, or higher oligomers fromthe compounds of formula I. In some embodiments, all of the hydrolysablegroups may be hydrolyzed. In some of these embodiments (e.g., in theabsence of filler), each Z is independently selected from the groupconsisting of hydroxyl and —O— covalently bonded to Si on anothercompound of formula I (that is, forming a siloxane bond (Si—O—Si)between two molecules of formula I.) The silanol groups typicallyparticipate in bonding interactions with silanol groups or other metalhydroxide groups on the surface of inorganic filler particles disclosedherein. The bonding interaction may be through a covalent bond (e.g.,through a condensation reaction), through hydrogen bonding, or through acombination thereof. It is reported in Polymer Interface and Adhesion,Souheng Wu, Marcel Dekker, Inc., New York, 1982, p. 416, that hydrogenbonding of the silanol groups to a glass surface usually occurs first,and then condensation reactions between silanol groups of adjacentsilane molecules can form a polysiloxane monolayer on the glass surface.Hydrogen bonded silanols and condensed polysiloxanes also occurs in theupper layers, and the silanes surrounding the particles may be hydrogenbonded or covalently bonded. This phenomenon also occurs with othermaterials that bear hydroxyl groups on the surface (that is, other thanglass). Accordingly, in some embodiments, particularly of treated filleror methods of making a treated filler, each Z or Z¹ is independentlyselected from the group consisting of hydroxyl, alkoxy, —O— covalentlybonded to the surface of the filler, and —O— covalently bonded to Si onanother compound of formula I (that is, forming a siloxane bond(Si—O—Si) between two molecules of formula I).

For any of the embodiments in which W is a silane (—Si(Y)_(x)(Z)_(3-x))or (—Si(Y)_(x)(Z¹)_(3-x)), x is 0 or 1. Typically x is 0.

Compounds of formulas I can be prepared, for example, beginning with anester represented by formula X

which is commercially available, for example, from Winchem IndustrialCo. Ltd, China, and China Langchem Inc., China as “DISPERSE RED 177”.This compound can be hydrolyzed under known saponification conditions toprovide the hydroxyl compound, an example of a compound shown below informula XI. Alternatively, compounds of formula I can be prepared bytreating commercially available 2-amino-6-nitrobenzothiazole withnitrosyl sulfuric acid solution prepared in situ from sodium nitrite inconcentrated sulfuric acid according to the method described in Chen, L.et al. Dyes and Pigments, 2007, vol. 73, pages 338 to 343. The reactioncan conveniently be carried out in a mixture of dichloroacetic acid andglacial acetic acid or a mixture of phosphoric acid and acetic acidafter cooling below room temperature. The resultant diazonium sulfatesalt can be coupled with N-(2-cyanoethyl)-N-(2-hydroxyethyl)aniline.Other N-(2-cyanoethyl)-N-(2-hydroxyalkyl)-anilines, which can beprepared by known methods, can also be useful in the coupling reaction.

The resultant compounds of formula XI:

can be converted to compounds according to formula I using a variety ofknown synthetic methods. For example, compounds of formula XI can betreated with isocyanatoalkyl silanes to provide compounds of formula Iin which X is alkylene interrupted by a —O—C(O)—NR¹— and W is—Si(Y)_(x)(Z)_(3-x). Such reactions can be carried out in the presenceof tin compounds (e.g., dibutyltin dilaurate) at ambient temperaturealthough the reaction can also be carried out in the absence of acatalyst or promoter. Isocyanato alkylene esters are also useful toprovide a compound of formula I in which X is alkylene interrupted by a—O—C(O)—NR¹— and W is a carboxylic acid group. Some of theseisocyanatoalkylene esters (e.g., ethyl 3-isocyanatopropionate) arecommercially available. Others may be prepared by conventional methods.Hydrolysis of the ester using conventional methods can provide acompound in which W is a carboxylic acid group.

Compounds of formula XI can also react with carboxylic acids and phenolsunder Mitsunobu reaction conditions. Typically the Mitsunobu coupling iscarried out in the presence of triphenyl phosphine and diisopropylazodicarboxylate or diethyl azodicarboxylate in a suitable solvent. Thereaction can conveniently be carried out at or below ambienttemperature. Under these conditions compounds of formula XI can bereacted, for example, with 5-sulfopentanoic acid, sulfoacetic acid, or asalt or ester of the sulfonic acid group of these to provide a compoundin which X is alkylene interrupted by —O—C(O)—, and W is a sulfonic acidgroup. When an ester of the sulfonic acid is used, exclusion of waterfrom the reaction mixture may be beneficial, and the product sulfonicacid ester can be hydrolyzed after the coupling reaction usingconventional methods. The Mitsunobu coupling reaction can also becarried out with phenols. For example, compounds of formula XI can betreated with methyl 3-(4-hydroxyphenyl)propionate or methyl4-hydroxyphenylacetate followed by hydrolysis of the ester to provide acompound of formula I in which X is alkylene interrupted by —O— andarylene, and W is a carboxylic acid group. Reaction of a compound offormula XI with hydroquinone may also be useful. After purification ofthe statistical mixture of reaction products of the compound of formulaXI and hydroquinone, a compound of formula I in which X is—CH₂CH₂—O—C₆H₄—, and W is OH can be treated with epichlorohydrin underbasic conditions to provide a compound in which X is—CH₂CH₂—O—C₆H₄—OCH₂—, and W is an epoxy group.

The hydroxyl group in the compound of formula XI can also be convertedto an amine or thiol using standard functional group manipulation. Theresultant amines or mercaptans can be reacted with isocyanatoalkylsilanes as described above, haloalkyl silanes, or with acrylatefunctional alkylsilanes to provide X groups in which alkylene isinterrupted by thioether (i.e., —S—), amine (i.e., —NR¹—), urea (i.e.,—(R¹)N—C(O)—N(R¹)—), and/or ester (—C(O)—O—), and W is(—Si(Y)_(x)(Z)_(3-x)) in the compounds of formula I. The resultantamines or mercaptans can also be reacted with alpha, beta-unsaturatedcarboxylic acids, phosphonic acids, and sulfonic acids to providecompounds in which W is sulfonic acid group, phosphonic acid group, or acarboxylic acid group, and X is alkylene interrupted by amine orthioether.

The hydroxyl group in the compound of XI can also be converted to a goodleaving group (e.g., mesylate or tosylate) and treated withamino-functional silanes or amino-functional acids or their salts oresters. For example, the mesylate of the compound of formula XI canreact with 2-aminoethylsulfonic acid, aminomethyl phosphonic acid,2-aminoethyl phosphonic acid, 3-aminopropyl phosphonic acid, or salts(e.g., sodium salt) or esters of any of these acids to provide acompound in which X is alkylene interrupted with —N(H)—, and W is asulfonic acid group, phosphonic acid group, or an ester thereof. Themesylate or tosylate of the compound of formula XI can react withdiamines to provide a compound of formula XI in which W is an aminogroup. For example, an alkylene diamine can be reacted with the mesylateof the compound of formula XI, and the resulting mixture can be purifiedto provide a compound in which X is alkylene interrupted with —N(R¹)—,and W is —NHR¹. Alternatively, one amino group can be protected beforethe reaction of the diamine with the mesylate of the compound of formulaXI, and the resultant product can be deprotected to provide the compoundin which W is —N(R¹)—. Phosphite esters can also be useful nucleophilesto displace the activated hydroxyl group and provide, after hydrolysisof the ester groups, compounds of formula I in which X is alkylene and Wis a phosphonic acid group.

The compounds of formulas I are useful, for example, for treatingfillers, generally inorganic fillers. The fillers can be microfillers,nanofillers, macrofillers, or fibrous fillers. The fillers can be made,for example, of alumina, tin oxides, antimony oxides, silica, zirconia,titania, mixed oxides of any of these, glass, ceramics, a mineral suchas mica, wollastonite, talc, clay, and combinations of any of thesefillers. The term “ceramic” refers to glasses, crystalline ceramics,glass-ceramics, and combinations thereof. Alumina, tin oxides, antimonyoxides, silica, zirconia, titania, mixed oxides of any of these, and theminerals can be of any desired size, including particles having anaverage size above 1 micrometer, between 100 nanometers (nm) and 1micrometer, and below 100 nm. In the treated fillers according to thepresent disclosure, the compound of formula I can be attached to thefiller covalently, ionically or through strong physisorption.

In some embodiments, the compounds of formulas I are useful, forexample, for treating siliceous fillers. In these embodiments, typicallyW in formula I is a silane (—Si(Y)_(x)(Z)_(3-x)) or(—Si(Y)_(x)(Z¹)_(3-x)), in which Y, Z, Z¹, and x are as defined in anyof their embodiments described above. The siliceous filler may be silicaof any desired size, including particles having an average size above 1micrometer, between 100 nm and 1 micrometer, and below 100 nm.

Silica can include nanosilica and amorphous fumed silica, for example.In some embodiments, the siliceous filler comprises silica nanoparticleshaving a particle size of greater than 1 nm and up to 100 nm. Silicananoparticles can have a particle size from 5 nm to 75 nm or 10 nm to 30nm or 20 nm. Examples of commercially available nanosilica suitable fortreatment with a compound of formula I include those available fromNalco Chemical Co. (Naperville, Ill.) under the trade designation “NALCOCOLLOIDAL SILICAS”. For example, silicas include NALCO products 1040,1042, 1050, 1060, 2327 and 2329. Suitable fumed silicas include forexample, products available from DeGussa AG, (Hanau, Germany) under thetrade designation “AEROSIL”, for example, series OX-50, -130, -150, and-200, and from Cabot Corp. (Tuscola, Ill.) under the trade designations“CAB-O-SPERSE 2095”, “CAB-O-SPERSE A10 5”, and “CAB-O-SIL M5”.

In some embodiments, the siliceous filler comprises hollow glasselements, such as hollow spheres (e.g., microspheres) and spheroids.Examples of commercially available materials suitable for use as thehollow, glass elements include glass bubbles marketed by 3M Company,Saint Paul, Minn., as “3M GLASS BUBBLES” in grades K1, K15, K20, K25,K37, K46, S15, S22, S32, S35, S38, S38HS, S38XHS, S42HS, S42XHS, S60,S60HS, iM30K, iM16K, XLD3000, XLD6000, and G-65, and any of the HGSseries of “3M GLASS BUBBLES”; glass bubbles marketed by PottersIndustries, Carlstadt, N.J., under the trade designations “Q-CEL HOLLOWSPHERES” (e.g., grades 30, 6014, 6019, 6028, 6036, 6042, 6048, 5019,5023, and 5028); and hollow glass particles marketed by Silbrico Corp.,Hodgkins, Ill. under the trade designation “SIL-CELL” (e.g., grades SIL35/34, SIL-32, SIL-42, and SIL-43). Solid glass spheres are also usefulas treated fillers according to the present disclosure, for example,solid glass spheres available from Cospheric LLC, Santa Barbara, Calif.as “SODA LIME SOLID GLASS MICROSPHERES”, “BOROSILICATE SOLID GLASSMICROSPHERES”, “BARIUM TITANATE GLASS SPHERES”, and “E GLASS SPHERES”.

In some embodiments, the siliceous filler comprises hollow, ceramicelements made from ceramics such as alumina silicates. In someembodiments, the discrete, hollow, ceramic elements are aluminosilicatemicrospheres extracted from pulverized fuel ash collected fromcoal-fired power stations (i.e., cenospheres). Useful cenospheresinclude those marketed by Sphere One, Inc., Chattanooga, Tenn., underthe trade designation “EXTENDOSPHERES HOLLOW SPHERES” (e.g., grades SG,MG, CG, TG, HA, SLG, SL-150, 300/600, 350 and FM-1). Other usefulhollow, ceramic spheroids include silica-alumina ceramic hollow sphereswith thick walls marketed by Valentine Chemicals of Lockport, La., asZEEOSPHERES CERAMIC MICROSPHERES in grades N-200, N-200PC, N-400, N-600,N-800, N1000, and N1200. Solid ceramic spheres are also useful astreated fillers according to the present disclosure, for example,ceramic microspheres marketed by 3M Company under the trade designation“3M CERAMIC MICROSPHERES” (e.g., grades W-610 and W-410).

The hollow glass or ceramic elements may have one of a variety of usefulsizes but typically has a maximum dimension of less than 10 millimeters(mm), more typically less than one mm. In some embodiments, the hollowglass elements have a maximum dimension in a range from 0.1 micrometerto one mm, from one micrometer to 500 micrometers, from one micrometerto 300 micrometers, or even from one micrometer to 100 micrometers. Themean particle size of the hollow, glass elements may be, for example, ina range from 5 to 250 micrometers (in some embodiments from 10 to 110micrometers, from 10 to 70 micrometers, or even from 20 to 50micrometers).

In some embodiments, the siliceous filler is a macrofiller prepared, forexample, by grinding or crushing quartz, glass, borosilicate, orceramics to a desired size range (e.g., in a range from 0.8 micrometersto 2 micrometers. The siliceous filler may also be glass or ceramicfibers. Such fibers may have, for example, diameters in a range from 2micrometers to 50 micrometers, in some embodiments 5 micrometers to 25micrometers and lengths of at least about 500 micrometers. In someembodiments, fibers from an essentially continuous mat, which may haveundetermined length, are useful. In some embodiments, the fibers have alength in a range from 1/16 inch (1.6 mm) to 1.5 inches (38.1 mm) long.In some embodiments, the fibers have a length in a range from 1/16 inch(1.6 mm) to about 0.5 inch (12.7 mm). In other embodiments, the fibershave a length in a range from one inch (25.4 mm) to 1.5 inches (38.1mm).

It is typically useful to treat the siliceous filler with a compound offormula I in which W is a silane such that approximately a monolayer ofthe dye is attached to the surface of a filler particle. For example, inembodiments in which the siliceous filler includes glass bubbles, ingeneral, one equivalent of the compound of formula I should be used perhydroxyl group on the glass bubbles. Using this stoichiometry, multiplelayers of siloxane on the surface of the glass bubbles, which may leadto inaccessibility of some of the dye in a free-radical reaction,described further below, can be avoided.

In some embodiments, the compounds of formulas I are useful, forexample, for treating zirconia. In some of these embodiments, theinorganic filler treated with a compound of formula I comprises zirconiananoparticles. Zirconia nanoparticles can have a particle size from 5 nmto 50 nm, 5 nm to 15 nm, or about 10 nm. Zirconias suitable fortreatment with a compound of formula I are commercially available, forexample, from Nalco Chemical Co. under the trade designation “NALCOOOSSOO8”. In some embodiments, the inorganic filler treatment with acompound of formula I comprises zirconia hollow ceramic microspheres.

In some embodiments, the compounds of formulas I are useful, forexample, for treating titania, antimony oxides, alumina, tin oxides,and/or mixed metal oxide fillers. Such fillers can have a variety ofuseful sizes as described above. In some embodiments, the titania,antimony oxides, alumina, tin oxides, and/or mixed metal oxide fillerscomprise nanoparticles having a particle size or associated particlesize from 5 nm to 50 nm, or 5 nm to 15 nm, or about 10 nm. Mixed metaloxides suitable for treatment with a compound of formula I arecommercially available, for example, from Catalysts & ChemicalIndustries Corp., (Kawasaki, Japan) under the product designation“OPTOLAKE 3”.

Inorganic fillers may be treated with compounds of formulas I using avariety of methods. The type of treatment agent of formula I and methodare determined, in part, by the chemical nature of the filler surface.As described above, compounds of formulas I in which W is a silane areuseful for treating siliceous fillers. Compounds of formulas I in whichW is a silane or an acid group (e.g., carboxylic acid, sulfonic acid, orphosphonic acid) may be useful, for example, for treating zirconia andminerals such as mica, wollastonite, talc, and clay. The required amountof the compound of formula I is dependent upon several factors includingparticle size, particle type, and the particular compound of formula I.In general it is useful for approximately a monolayer of the compound offormula I to be attached to the surface of the particle. The attachmentprocedure or reaction conditions required also depend on the particularcompound of formula I used. When W is a carboxylic acid, elevatedtemperature or extended time may not be necessary.

For treating siliceous filler (e.g., hollow glass or ceramic elements),zirconia, or a mineral such as mica, wollastonite, talc, clay with thecompound of formula I, in which W is a silane, a useful method typicallyincludes combining the compound of formula I with the siliceous fillerin a medium comprising water. Hydrolysis of the Z groups in a compoundof formula I typically generates silanol groups, which participate incondensation reactions to form siloxanes and/or participate in bondinginteractions with silanol groups on siliceous fillers. Hydrolysis canoccur, for example, in the presence of water optionally in the presenceof an acid or base. The water necessary for hydrolysis is typicallyadded to a composition containing the compound of formula I and thesiliceous filler, although, in some cases, the water may be adsorbed tothe surface of the filler, or may be present in the atmosphere to whichthe filler is exposed (e.g., an atmosphere having a relative humidity ofat least 10%, 20%, 30%, 40%, or even at least 50%). The rate of thecondensation reaction is typically dependent upon temperature, pH, andthe concentration of the compound of formula I. In some embodiments, itis useful to surface treat filler with a compound or formula I in whichW is a silane at elevated temperatures under acidic or basic conditionsfor approximately one to 24 hours. The surface modification of zirconiawith a compound of formula I in which W is a silane can be carried outby heating under acid conditions for a suitable period of time afterwhich the dispersion is combined with aqueous ammonia (or other base).This method allows removal of the acid counter ion from the zirconiasurface as well as reaction with the silane. The particles may then beseparated from the liquid phase.

The surface modification of the particles in the colloidal dispersion(e.g., nanoparticles) can be accomplished in a variety of ways. Forexample, mixing an inorganic dispersion with a compound of formula Ioptionally in a co-solvent (e.g., 1-methoxy-2-propanol, ethanol,isopropanol, ethylene glycol, N,N-dimethylacetamide andN-methyl-2-pyrrolidinone) can be useful. The co-solvent can enhance thesolubility of the compound of formula I as well as the treatedparticles. The mixture comprising the inorganic sol and compound offormula I is subsequently reacted at room temperature or an elevatedtemperature, with or without mixing. Conveniently, the mixture can bereacted at about 85° C. for about 24 hours, resulting in the surfacemodified sol. When metal oxides are treated with a compound of formulaI, the surface treatment of the metal oxide can involve the adsorptionof acidic molecules (e.g., compounds in which W is a sulfonic acidgroup, a phosphoric acid group, or carboxylic acid group) to theparticle surface, which can take place, for example, at roomtemperature.

In some embodiments, an inorganic filler can be treated with a compoundof formula I using a two-step process in which first the inorganicfiller is treated with a surface treatment agent, and the resultingfunctionalized filler is treated with a compound of formula I. Forexample, using any of the methods described above a siliceous filler orzirconia as described in any of the aforementioned embodiments may betreated with 3-(methacryloyloxy)propyltrimethoxysilane,3-acryloxypropyltrimethoxysilane,3-(methacryloyloxy)propyltriethoxysilane, 3-(methacryloyloxy)propylmethyldimethoxysilane, 3-(acryloyloxypropyl)methyldimethoxysilane,3-(methacryloyloxy)propyldimethylethoxysilane, 3-(methacryloyloxy)propyldimethylethoxysilane, 3-glycidoxypropyltrimethoxysilane, acrylicacid, methacrylic acid, or beta-carboxyethylacrylate. The resultingacrylate-, methacrylate-, or epoxy-functional filler can then be treatedwith a compound of formula I in which W is a hydroxyl or amino groupusing conventional methods.

Treated fillers according to the present disclosure can be useful incompositions including a curable polymeric resin, for example. Thecurable polymeric resins are curable by free-radical polymerization.Examples of suitable curable polymeric resin include acrylics, epoxies,urethanes, silicones, vinyl esters, polyesters, ene-thiol compositions,and combinations thereof. As would be understood by a person of ordinaryskill in the art, a vinyl ester is a resin produced by theesterification of an epoxy resin with an unsaturated monocarboxylicacid.

Ene-thiol compositions, which are also referred to as thiol-enecompositions, are those compositions comprising a polythiol and at leastone unsaturated compound comprising two or more carbon-carbon doublebonds, carbon-carbon triple bonds, or a combination thereof. Suitableunsaturated compounds include dienes, diynes, divinyl ethers, diallylethers, ene-ynes, and trifunctional versions of any of these.Combinations of any of these groups may also be useful. A polythiol is acompound having at least two mercaptan groups (e.g., 2, 3, or 4mercaptan groups). Polythiols include monomeric compounds and oligomericcompounds. A monomeric polythiol may be an alkylene, arylene,alkylarylene, arylalkylene, or alkylenearylalkylene having at least twomercaptan groups, wherein any of the alkylene, alkylarylene,arylalkylene, or alkylenearylalkylene are optionally interrupted by oneor more ether (i.e., —O—), thioether (i.e., —S—), or amine (i.e., —NR¹—)groups and optionally substituted by alkoxy or hydroxyl. A usefuloligomeric or polymeric polythiol may be a polythioether made, forexample, by reacting dithiols with dienes, diynes, divinyl ethers,diallyl ethers, ene-ynes, or combinations of these under free-radicalconditions, by reacting dithiols with diepoxides, or by a combination ofsuch methods. See, for example, polythioethers in U.S. Pat. No.4,366,307 (Singh et al.), U.S. Pat. No. 4,609,762 (Morris et al.), U.S.Pat. No. 5,225,472 (Cameron et al.), U.S. Pat. No. 5,912,319 (Zook etal.), U.S. Pat. No. 5,959,071 (DeMoss et al.), U.S. Pat. No. 6,172,179(Zook et al.), and U.S. Pat. No. 6,509,418 (Zook et al.). A usefuloligomeric or polymeric polythiol may also be a polysulfide prepared,for example, by the condensation of sodium polysulfide withbis-(2-chloroethyl) formal. See, for example, in U.S. Pat. No. 2,466,963(Patrick et al); U.S. Pat. No. 2,789,958 (Fettes et al); U.S. Pat. No.4,165,425 (Bertozzi); and U.S. Pat. No. 5,610,243 (Vietti et al.).Ene-thiol compositions cure by free-radical initiated polymerization,for example, in the presence of a free-radical initiator.

The curable polymeric resin can include one or more non-reactivepolymeric materials, as desired, for a particular application.Compositions including a curable polymeric resin and a filler accordingto the present disclosure may be combined with a free-radical initiatorto cure the composition as described in further detail below. Treatedfillers according to the present disclosure can be included incompositions including a curable polymeric resin in an amount of atleast 1, 5, 10, 20, 30, 40, or 50 percent by weight up to about 75percent by weight, based on the total weight of the composition.Mixtures of more than one type treated filler may be used together inthe curable polymeric resins.

For many embodiments of the treated fillers according to the presentdisclosure, the fillers can be mixed in a curable polymeric resin usingconventional mixing. When the treated fillers are prepared from acolloidal dispersion (e.g., nanoparticles) a variety of methods forincorporating the treated fillers into a curable polymeric resin may beuseful. For example, a solvent exchange procedure may be useful. In asolvent exchange method, the curable polymeric resin can be added to thesurface modified sol, followed by removal of the water and co-solvent(if used) via evaporation, thus leaving the particles dispersed in thecurable polymeric resin. The evaporation step can be accomplished, forexample, via distillation, rotary evaporation, or oven drying. Inanother example, the surface modified particles can be extracted into awater immiscible solvent followed by solvent exchange. Another methodinvolves the drying of the modified particles into a powder, followed bythe addition of the curable polymeric resin into which the particles aredispersed. Drying can be carried out using a variety of suitable methods(e.g., oven drying or spray drying).

One application of compositions according to the present disclosure thatinclude curable polymeric resins are curable body repair materialsuseful in the repair of damaged vehicles and other equipment (e.g.,cars, trucks, watercraft, windmill blades, aircraft, recreationalvehicles, bathtubs, storage containers, and pipelines). Curable bodyrepair materials can include two reactive components (e.g., a curablepolymeric resin and catalyst or initiator) which are mixed together toform the curable body repair material. The volumetric ratio of thereactive components may be in the range of, e.g., 1:1 or higher (wherehigher is, e.g., 2:1, 3:1, etc.) for epoxy or urethane compounds and maybe 20:1 or higher, or 25:1 or higher, or 30:1 or higher for unsaturatedpolyesters with a peroxide catalyst as an initiator. The curable bodyrepair materials may include additives to enhance adhesion of thecurable body material to common repair surfaces (e.g., aluminum,galvanized steel, E-coats, primers, and paints). The adhesion promotingadditives may have, for example, anhydride functionality, silanefunctionality, or amine functionality and may or may not be covalentlyincorporated into the base resin.

In some embodiments, the curable polymeric resin is an unsaturatedpolyester resin. Unsaturated polyester resins include a polyestergenerally formed by a polycondensation reaction of an unsaturateddicarboxylic acid (e.g., maleic acid or fumaric acid) with a dihydroxycompound (e.g., a glycol) or diamine. Saturated dicarboxylic acids orequivalents (e.g., phthalic anhydride) can also be included. In someembodiments, the curable polymeric resin further includes at least oneof styrene monomer, a substituted styrene monomer (e.g., alpha-methylstyrene, p-methyl styrene, or divinylbenzene), an acrylate monomer, amethacrylate monomer, or any compound that can be copolymerized with theunsaturated polyester resin. Illustrative curable, unsaturated polyesterbased compositions are described in U.S. Pat. No. 6,063,864 (Mathur etal.); U.S. Pat. No. 5,456,947 (Parish et al.); U.S. Pat. No. 4,980,414(Naton); U.S. Pat. No. 5,028,456 (Naton); and U.S. Pat. No. 5,373,036(Parish et al.). Other illustrative curable, unsaturated polyester basedcompositions are described in Int. Pat. Appl. Pub. No. WO 95/19379(Ruggeberg).

Body filler compositions may include other filler in addition to thetreated filler according to the present disclosure. In some embodiments,the composition according to the present disclosure further includes atleast one of polymer beads, hollow polymeric elements, sodiummetaborate, polymer fibers, carbon or metal fibers, dolomite, or calciumcarbonate. In some embodiments, the composition according to the presentdisclosure also includes any one of the fillers described above (e.g.,alumina, tin oxides, antimony oxides, silica, zirconia, titania, mixedoxides of any of these, minerals (e.g., mica, wollastonite, talc, andclay), glass, ceramics, and combinations thereof) that is not treated.In some embodiments, it may be useful for the filler in the compositionincluding a curable polymeric resin to be limited to the treated filleraccording to the present disclosure. This may be useful, for example, tohelp visualize a color change in the composition as described in furtherdetail, below.

Compositions according to the present disclosure including a curablepolymeric resin and a treated filler disclosed herein can furtherinclude a free-radical initiator. Any free-radical initiator may beuseful. In some embodiments, the free-radical initiator is an organicperoxide. Examples of useful organic peroxides include hydroperoxides(e.g., cumene, tert-butyl or tert-amyl hydroperoxide), dialkyl peroxides(e.g., di-tert-butyl, dicumylperoxide, or cyclohexyl peroxide),peroxyesters (e.g., tert-butyl perbenzoate, tert-butylperoxy-2-ethylhexanoate, tert-butyl peroxy-3,5,5-trimethylhexanoate,tert-butyl monoperoxymaleate, or di-tert-butyl peroxyphthalate),peroxycarbonates (e.g., tert-butylperoxy 2-ethylhexylcarbonate,tert-butylperoxy isopropyl carbonate, or di(4-tert-butylcyclohexyl)peroxydicarbonate), ketone peroxides (e.g., methyl ethyl ketoneperoxide, 1,1-di(tert-butylperoxy)cyclohexane,1,1-di(tert-butylperoxy)-3,3,5-trimethylcyclohexane, and cyclohexanoneperoxide), and diacylperoxides (e.g., benzoyl peroxide or laurylperoxide). The organic peroxide may be selected, for example, based onthe temperature desired for use of the organic peroxide andcompatibility with a curable polymeric resin desired to be cured.Combinations of two or more organic peroxides may also be useful.

The free-radical initiator may also be a photoinitiator. Examples ofuseful photoinitiators include benzoin ethers (e.g., benzoin methylether or benzoin butyl ether); acetophenone derivatives (e.g.,2,2-dimethoxy-2-phenylacetophenone or 2,2-diethoxyacetophenone);1-hydroxycyclohexyl phenyl ketone; and acylphosphine oxide derivativesand acylphosphonate derivatives (e.g.,bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide,diphenyl-2,4,6-trimethylbenzoylphosphine oxide,isopropoxyphenyl-2,4,6-trimethylbenzoylphosphine oxide, or dimethylpivaloylphosphonate). Many photoinitiators are available, for example,from BASF (Florham Park, N.J.), under the trade designation “IRGACURE”.The photoinitiator may be selected, for example, based on the desiredwavelength for curing and compatibility with a curable polymeric resindesired to be cured.

For convenience, compositions according to the present disclosureincluding a curable polymeric resin and a treated filler disclosedherein can be combined with a formulation including the free-radicalinitiator and a diluent. The diluent can be a plasticizer, mineralspirits, water, or a solvent such as N-methyl-2-pyrrolidone,tetrahydrofuran, or ethyl acetate. Some pastes including a diluent and aperoxide such as benzoyl peroxide, ketone peroxides (e.g., methyl ethylketone peroxide), hydroperoxides (e.g., cumene hydroperoxide),peroxyesters (e.g., t-butyl peroxy-2-ethylhexanoate), and diperoxyketalsare sold commercially.

For repairing an automobile, for example, a technician typically mixesthe two reactive components and then uses a squeegee to spread therepair compound onto the surface of the vehicle to roughly match thecontour of the surface. As the curable polymeric resin reacts with thecurative or initiator, it hardens to a state where it can be shaped tomatch the contour of the vehicle before it was damaged. During thishardening process, the body filler typically transitions from a state ofsoft, gelled material to a state of moderately hard material that isrelatively easy to shape with an abrasive article (e.g., sandpaper) to astate of hard material. In some embodiments, the body filler is a filledunsaturated polyester resin that is mixed with a peroxide to facilitatecrosslinking at room temperature.

The process of repairing dents using body filler can present challenges.Body filler typically requires handling in a relatively narrow timewindow. Premature sanding of body filler before it has reached acritical amount of cure results in sandpaper becoming plugged therebyreducing its effectiveness, the surface of the body filler becomingrough, and sometimes the body filler peeling away from the surface ofthe vehicle. If this situation occurs, then typically the body fillerhas to be partially removed (usually by sanding) such that another layerof body filler can be put on top and properly shaped. Waiting too longbefore shaping the body filler can lengthen the time required to repairthe dent as the body filler becomes hardened to a point where thematerial can be difficult to shape. Most body filler systems are nowformulated to cure to a good shaping state in a relatively short amountof time (e.g., 4 to 12 minutes). Identifying the time period when thebody filler has transitioned into the state where it is relatively easyto shape is important to speed up that part of the repair process.

Other processes that may be enhanced by recognizing the extent of curein a curable composition include curing medical adhesives and dentalcomposites or adhesives. In some of these applications, the curablecomposition includes a photoinitiator. In some embodiments, thesecompositions include acrylate, methacrylate, acrylamide, ormethacrylamide monomers in combination with oligomeric urethaneacrylates or methacrylate or other functional oligomers.

In some embodiments, compositions according to the present disclosureincluding an ene-thiol curable composition and a treated fillerdisclosed herein can be useful as sealants, for example, aviation fuelresistant sealants. Aviation fuel resistant sealants are widely used bythe aircraft industry for many purposes. Principal among these uses arethe sealing of integral fuel tanks and cavities, the sealing of thepassenger cabin to maintain pressurization at high altitude, and for theaerodynamic smoothing of the aircraft's outer surfaces. In some of theseapplications, the curable composition includes a photoinitiator.

In compositions that are light cured, the compositions according to thepresent disclosure also provide the advantage that they can indicatewhen they have been exposed to a curing light. In these cases, thedisappearance or muting of the color can indicate that the compositionshave been exposed to the curing light. The color change in the presentlydisclosed compositions indicates that free radicals have been generated,which may distinguish these compositions from those that undergophotobleaching. This feature can be beneficial when a manufacturing linehas been stopped, for example, so that operators can easilydifferentiate exposed and unexposed compositions.

In some embodiments, compositions according to the present disclosureinclude a treated filler disclosed herein and one or more monomers(e.g., styrene, a substituted styrene, acrylate, methacrylate,acrylamide, or methacrylamide monomers). In some of these embodiments,the composition further includes a free-radical initiator.

The fillers treated with a compound of formula I according to thepresent disclosure can be useful for indicating curing in theapplications described above. The compounds of formulas I change colorin the presence of free-radicals, and thus can directly indicate cure bycorrelation of the concentration of free-radicals in the system. Fillerstreated with compounds of formulas I have an initial colored state and aless colored or colorless final state, as demonstrated in the examples,below. For many applications, such as auto repair or dentalapplications, a colorless or nearly colorless final state is highlydesirable. In auto repair, a cure indicator that retains a specificcolor in its cured state can be problematic when it comes to painting.Furthermore, since the compound of formula I is bonded to the filler, itadvantageously does not migrate out of the cured system over time.

Accordingly, the present disclosure also provides a method fordetermining degree of cure of a curable polymeric resin, including anyof the curable polymeric resins described above. The method includesproviding a composition comprising a curable polymeric resin, afree-radical initiator, and a treated filler according to the presentdisclosure in an amount sufficient to provide the composition with afirst absorbance at a wavelength in a range from 400 nanometers to 700nanometers. The wavelength may be in a range, for example, from 450nanometers to 650 nanometers, typically in a range from 500 nanometersto 550 nanometers. Allowing the composition to cure or curing thecomposition provides a cured composition that has a second absorbance atthe wavelength that is different from the first absorbance. In someembodiments, the absorbance at the selected wavelength is decreased byat least 20, 25, 30, 35, 40, 45, or 50 percent or more. The initial andfinal absorbance can be measured, for example, using a UV/VISspectrometer or a colorimeter. A composition having an absorbance at awavelength in a range from 400 nanometers to 700 nanometers wouldtypically be perceived by the human eye as a particular color. In someembodiments, a color in the composition is no longer visible in thecured composition. In these embodiments, a difference between the secondabsorbance and the first absorbance is visually determined. In someembodiments, providing the composition includes mixing the curablepolymeric resin including the treated filler with a curative comprisingthe free-radical initiator. The free-radical initiator may be any ofthose described above, and the curative may also include any of thediluents described above. Advantageously, mixing can be carried outuntil the visible color of the treated filler is uniformly dispersed inthe composition.

Some Embodiments of the Disclosure

In a first embodiment, the present disclosure provides a compoundrepresented by formula:

wherein

-   -   R is hydrogen or alkyl;    -   X is alkylene, arylalkylene, or alkylarylene, wherein alkylene,        arylalkylene, and alkylarylene are optionally interrupted by at        least one of an ether, thioether, amine, amide, ester,        thioester, carbonate, thiocarbonate, carbamate, thiocarbamate,        urea, or thiourea, and wherein alkylene is optionally        interrupted by arylene;    -   W is hydroxyl, a sulfonic acid group, a phosphonic acid group, a        carboxylic acid group, —NHR¹, epoxy, or —Si(Y)_(x)(Z)_(3-x);    -   R¹ is hydrogen, alkyl, aryl, arylalkylenyl, or alkylarylenyl;    -   Y is alkyl, aryl, arylalkylenyl, or alkylarylenyl;    -   each Z is independently halide, hydroxyl, alkoxy, aryloxy,        acyloxy, polyalkyleneoxy, or —O bonded to another silicon atom        to form a siloxane, wherein alkoxy and acyloxy are optionally        substituted by halogen, and wherein aryloxy is optionally        substituted by halogen, alkyl, or haloalkyl; and    -   x is 0 or 1,        with the proviso that when X is ethylene, W is other than        hydroxyl.

In a second embodiment, the present disclosure the compound of the firstembodiment, represented by formula:

wherein

-   -   R is hydrogen or alkyl;    -   X is alkylene, arylalkylene, or alkylarylene, wherein alkylene,        arylalkylene, and alkylarylene are optionally interrupted by at        least one of an ether, thioether, amine, amide, ester,        thioester, carbonate, thiocarbonate, carbamate, thiocarbamate,        urea, or thiourea, and wherein alkylene is optionally        interrupted by arylene;    -   Y is alkyl, aryl, arylalkylenyl, or alkylarylenyl;    -   each Z is independently halide, hydroxyl, alkoxy, aryloxy,        acyloxy, polyalkyleneoxy, or —O bonded to another silicon atom        to form a siloxane, wherein alkoxy and acyloxy are optionally        substituted by halogen, and wherein aryloxy is optionally        substituted by halogen, alkyl, or haloalkyl; and    -   x is 0 or 1.

In a third embodiment, the present disclosure provides the compound ofthe first or second embodiment, wherein R is hydrogen.

In a fourth embodiment, the present disclosure provides the compound ofthe first embodiment, wherein W is —Si(Y)_(x)(Z)_(3-x).

In a fifth embodiment, the present disclosure provides the compound ofany one of the first to fourth embodiments, wherein x is 0, and whereinZ is alkoxy.

In a sixth embodiment, the present disclosure provides the compound ofany one of the first to fifth embodiments, wherein X is alkylene that isoptionally interrupted by at least one ether, ester, carbonate,carbamate, or arylene.

In a seventh embodiment, the present disclosure provides the compound ofany one of the first to sixth embodiments, wherein X is alkylene that isinterrupted by —O—C(O)—NH— and optionally interrupted by —O—.

In an eighth embodiment, the present disclosure provides a treatedfiller comprising the compound of any one of first to seventhembodiments at least one of covalently bonded, ionically bonded, orhydrogen-bonded to a filler.

In a ninth embodiment, the present disclosure provides treated fillercomprising:

a filler having on at least a portion of its surface a compound offormula

wherein

-   -   R is hydrogen or alkyl;    -   X is alkylene, arylalkylene, or alkylarylene, wherein alkylene,        arylalkylene, and alkylarylene are optionally interrupted by at        least one of an ether, thioether, amine, amide, ester,        thioester, carbonate, thiocarbonate, carbamate, thiocarbamate,        urea, or thiourea, and wherein alkylene is optionally        interrupted by arylene;    -   W is hydroxyl, a sulfonic acid group, a phosphonic acid group,        carboxylic acid group, —NHR¹, epoxy, or —Si(Y)_(x)(Z¹)_(3-x);    -   R¹ is hydrogen, alkyl, aryl, arylalkylenyl, or alkylarylenyl;    -   Y is alkyl, aryl, arylalkylenyl, or alkylarylenyl;    -   each Z¹ is independently halide, hydroxyl, alkoxy, aryloxy,        acyloxy, polyalkyleneoxy, —O— covalently bonded to the surface        of the filler, or —O— bonded to another silicon atom to form a        siloxane, wherein alkoxy and acyloxy are optionally substituted        by halogen, and wherein aryloxy is optionally substituted by        halogen, alkyl, or haloalkyl; and    -   x is 0 or 1,        and wherein the compound is at least one of covalently bonded,        ionically bonded, or hydrogen-bonded to the filler.

In a tenth embodiment, the present disclosure provides the treatedfiller of the ninth embodiment, wherein W is —Si(Y)_(x)(Z¹)_(3-x).

In an eleventh embodiment, the present disclosure provides the treatedfiller of the tenth embodiment, wherein each Z¹ is independentlyhydroxyl, alkoxy, —O— covalently bonded to the surface of the filler, or—O bonded to another silicon atom to form a siloxane.

In a twelfth embodiment, the present disclosure provides the treatedfiller of the tenth or eleventh embodiment, wherein x is 0.

In a thirteenth embodiment, the present disclosure provides the treatedfiller of any one of the ninth to twelfth embodiments, wherein X isalkylene that is optionally interrupted by at least one ether, ester,carbonate, carbamate, or arylene.

In a fourteenth embodiment, the present disclosure provides the treatedfiller of any one of the ninth to thirteenth embodiments, wherein R ishydrogen.

In a fifteenth embodiment, the present disclosure provides the treatedfiller of any one of the ninth to fourteenth embodiments, wherein X isalkylene that is optionally interrupted by at least one ether, ester,carbonate, or carbamate.

In a sixteenth embodiment, the present disclosure provides the treatedfiller of any one of the ninth to fifteenth embodiments, wherein X isalkylene that is interrupted by —O—C(O)—NH— and optionally interruptedby —O—.

In a seventeenth embodiment, the present disclosure provides the treatedfiller of any one of the eighth to sixteenth embodiments, wherein thefiller comprises at least one of alumina, tin oxides, antimony oxides,silica, zirconia, titania, mixed oxides of any of these, glass, orceramics.

In an eighteenth embodiment, the present disclosure provides the treatedfiller of any one of the eighth to sixteenth embodiments, wherein thefiller comprises at least one of mica, wollastonite, talc, or clay.

In a nineteenth embodiment, the present disclosure provides the treatedfiller of any one of the eighth to eighteenth embodiments, wherein thefiller is a siliceous filler, calcium carbonate, or sodium metaborate.

In twentieth embodiment, the present disclosure provides the treatedfiller of the nineteenth embodiment, wherein Z is —O bonded to anothersilicon atom on a surface of the filler forming a siloxane bond with thesurface.

In a twenty-first embodiment, the present disclosure provides thetreated filler of the nineteenth or twentieth embodiment, wherein thesiliceous filler comprises hollow glass elements.

In a twenty-second embodiment, the present disclosure provides acomposition comprising a curable composition and the treated filler ofany one of the eighth to twenty-first embodiments.

In a twenty-third embodiment, the present disclosure provides thecomposition of the twenty-second embodiment, wherein the curablecomposition comprises an unsaturated polyester resin.

In a twenty-fourth embodiment, the present disclosure provides thecomposition of the twenty-second embodiment, wherein the curablecomposition comprises a vinyl ester resin.

In a twenty-fifth embodiment, the present disclosure provides thecomposition any one of the twenty-second to twenty-fourth embodiments,further comprising at least one of styrene monomer, a substitutedstyrene monomer, an acrylate monomer, or a methacrylate monomer.

In a twenty-sixth embodiment, the present disclosure provides thecomposition of any one of the twenty-second to twenty-fifth embodiments,further comprising a free-radical initiator.

In a twenty-seventh embodiment, the present disclosure provides thecomposition of the twenty-sixth embodiment, wherein the free-radicalinitiator is an organic peroxide.

In a twenty-eighth embodiment, the present disclosure provides thecomposition of the twenty-sixth embodiment, wherein the free-radicalinitiator is a photoinitiator.

In a twenty-ninth embodiment, the present disclosure provides a methodfor determining degree of cure of a curable composition, the methodcomprising:

providing the composition of any one of the twenty-second totwenty-eighth embodiments, wherein the treated filler is present in anamount sufficient to provide the composition with a first absorbance ata wavelength in a range from 400 nanometers to 700 nanometers; and

allowing the composition to cure to provide a cured composition, whereinthe cured composition has a second absorbance at the wavelength that isdifferent from the first absorbance.

In a thirtieth embodiment, the present disclosure provides the method ofthe twenty-ninth embodiment, wherein providing the composition comprisesmixing the curable composition with the treated filler.

In a thirty-first embodiment, the present disclosure provides the methodof the thirtieth embodiment, wherein mixing is carried out until thecomposition is uniformly colored.

In a thirty-second embodiment, the present disclosure provides a methodof making a treated filler, the method comprising treating a filler witha compound represented by formula:

wherein

-   -   R is hydrogen or alkyl;    -   X is alkylene, arylalkylene, or alkylarylene, wherein alkylene,        arylalkylene, and alkylarylene are optionally interrupted by at        least one of an ether, thioether, amine, amide, ester,        thioester, carbonate, thiocarbonate, carbamate, thiocarbamate,        urea, or thiourea, and wherein alkylene is optionally        interrupted by arylene;    -   W is hydroxyl, a sulfonic acid group, a phosphonic acid group,        carboxylic acid, —NHR¹, epoxy, or —Si(Y)_(x)(Z¹)_(3-x);    -   R¹ is hydrogen, alkyl, aryl, arylalkylenyl, or alkylarylenyl;    -   Y is alkyl, aryl, arylalkylenyl, or alkylarylenyl;    -   each Z¹ is independently halide, hydroxyl, alkoxy, aryloxy,        acyloxy, polyalkyleneoxy, —O— bonded to another silicon atom to        form a siloxane, or —O— covalently bonded to the surface of the        filler, wherein alkoxy and acyloxy are optionally substituted by        halogen, and wherein aryloxy is optionally substituted by        halogen, alkyl, or haloalkyl; and    -   x is 0 or 1.

In a thirty-third embodiment, the present disclosure provides the methodof the thirty-second embodiment, wherein R is hydrogen.

In a thirty-fourth embodiment, the present disclosure provides themethod of the thirty-second or thirty-third embodiment, wherein X isalkylene that is optionally interrupted by at least one ether, ester,carbonate, carbamate, or arylene.

In a thirty-fifth embodiment, the present disclosure provides the methodof any one of the thirty-second to thirty-fourth embodiments, wherein Xis alkylene that is interrupted by —O—C(O)—NH— and optionallyinterrupted by —O—.

In a thirty-sixth embodiment, the present disclosure provides the methodof any one of the thirty-second to thirty-fifth embodiments, wherein thecompound is at least one of covalently bonded, ionically bonded, orhydrogen-bonded to the filler.

In a thirty-seventh embodiment, the present disclosure provides themethod comprising the compound of any one of thirty-second tothirty-sixth embodiments, wherein the filler comprises at least one ofalumina, tin oxides, antimony oxides, silica, zirconia, titania, mixedoxides of any of these, glass, or ceramics.

In a thirty-eighth embodiment, the present disclosure provides themethod of any one of thirty-second to thirty-sixth embodiments, whereinthe filler comprises at least one of mica, wollastonite, talc, or clay.

In a thirty-ninth embodiment, the present disclosure provides the methodof any one of the thirty-second to thirty-eighth embodiments, whereinthe filler is a siliceous filler, calcium carbonate, or sodiummetaborate.

In a fortieth embodiment, the present disclosure provides the method ofthe thirty-ninth embodiment, wherein the siliceous filler compriseshollow glass elements.

In a forty-first embodiment, the present disclosure provides the methodof the thirty-ninth or fortieth embodiment, wherein the compound isrepresented by formula:

wherein

-   -   R is hydrogen or alkyl;    -   X is alkylene, arylalkylene, or alkylarylene, wherein alkylene,        arylalkylene, and alkylarylene are optionally interrupted by at        least one of an ether, thioether, amine, amide, ester,        thioester, carbonate, thiocarbonate, carbamate, thiocarbamate,        urea, or thiourea, and wherein alkylene is optionally        interrupted by arylene;    -   Y is alkyl, aryl, arylalkylenyl, or alkylarylenyl;    -   Z¹ is halide, hydroxyl, alkoxy, aryloxy, acyloxy,        polyalkyleneoxy, —O— bonded to another silicon atom to form a        siloxane, or —O— covalently bonded to the surface of the filler,        wherein alkoxy and acyloxy are optionally substituted by        halogen, and wherein aryloxy is optionally substituted by        halogen, alkyl, or haloalkyl; and    -   x is 0 or 1.

In a forty-second embodiment, the present disclosure provides the methodof the forty-first embodiment, wherein x is 0, and wherein Z¹ is alkoxy.

In a forty-third embodiment, the present disclosure provides thecomposition of the twenty-second embodiment, wherein the curablecomposition is an ene-thiol composition.

In order that this disclosure can be more fully understood, thefollowing examples are set forth. It should be understood that theseexamples are for illustrative purposes only, and are not to be construedas limiting this disclosure in any manner.

EXAMPLES

Unless otherwise noted, all reagents were obtained or are available fromfine chemical vendors, such as: Sigma-Aldrich Company, St. Louis, Mo.;EMD Millipore Chemicals, Billerica, Mass.; Alfa Aesar, Ward Hill, Mass.;J. T. Baker, Phillipsburg, N.J.; BDH Merck Ltd., Poole, Dorset, UK, andCambridge Isotope Laboratories, Inc., Andover, Mass.; or may besynthesized by known methods. Unless otherwise reported, all ratios areby weight percent.

The following abbreviations are used to describe the examples: ° C.refers to degrees Centigrade, cm refers to centimeter, d₆-DMSO refers todeuterated dimethyl sulfoxide, mL refers to milliliter, mm refers tomillimeter, mmol refers to millimole, μL refers to microliter, μmolrefers to micromole, NMR refers to nuclear magnetic resonance, and Parefers to Pascal.

Synthesis of2-(4-(N-cyanoethyl-N-(2-hydroxyethyl)amino)phenylazo)-6-nitrobenzothia-zole

5.00 grams (25.6 mmol) 2-amino-6-nitrobenzothiazole was added to 66 mLof a 5:1 (by volume) solution of dichloroacetic acid:acetic acid in a250 mL flask and dissolved by heating to 50° C. for 15 minutes. Thesolution was cooled to 0° C. and slowly added, with constant stirringover a 10 minute period, to a 250 mL flask containing a solution of 1.94grams (28.1 mmol) sodium nitrite in 13 mL concentrated sulfuric acidheld at 0° C. After stirring for an additional 30 minutes, this solutionwas slowly added to a 250 mL flask containing a mixture of 4.20 grams(22.1 mmol) N-(2-cyanoethyl)-N-(2-hydroxyethyl)aniline in 13 mL aceticacid, also held at 0° C., and stirred for 1 hour. The reaction mixturewas then neutralized by the addition of a saturated aqueous sodiumcarbonate solution until the pH of the reaction mixture wasapproximately 7. The resulting precipitate was isolated by vacuumfiltration. The precipitate was dissolved in 200 mL methylene chloride,then dried by passing through a bed of anhydrous sodium sulfate,filtered, and condensed in a rotary evaporator. The resulting solid wasfurther purified by loading onto a 3 by 23 cm silica gel column, theneluting with an acetone:methylene chloride solution where the solventratio, by volume, was gradually changed from 10:90 to 30:70. Subsequentfractions containing the pure compound were combined, condensed underreduced pressure and dried under a vacuum of 0.3 mm mercury (40.0 Pa) atapproximately 21° C. to yield 4.30 grams of a purple solid, subsequentlyconfirmed by NMR spectroscopy to be2-(4-(N-cyanoethyl-N-(2-hydroxyethyl)amino)phenylazo)-6-nitrobenzothia-zole[¹H NMR (500 MHz, d₆-DMSO) δ 9.07 (dd, J=0.4, 2.4 Hz, 1H), 8.32 (dd,J=2.4, 8.9 Hz, 1H), 8.17 (dd, J=0.4, 8.9 Hz, 1H), 7.91 (d, J=9.4 Hz,2H), 7.11 (d, J=9.4 Hz, 2H), 4.99 (t, J=5.1 Hz, 1H), 3.95 (t, J=7.1 Hz,2H), 3.73-3.65 (m, 4H), 2.91 (t, J=6.9 Hz, 2H)].

Synthesis of [3-(triethoxysilyl)propyl]-carbamic acid2-{(2-cyanoethyl)-[4-(6-nitrobenzo-thiazol-2-ylazo)-phenyl]amino}-ethylester

140 μL (567 μmol) of 3-(triethoxysilyl)propyl isocyanate was added to a25 mL flask containing a solution of 0.2012 g (508 μmol)2-(4-(N-cyanoethyl-N-(2-hydroxyethyl)amino)-phenylazo)-6-nitrobenzothiazolein 10 mL dimethylsulfoxide. This reaction mixture was heated to 75° C.and stirred under a nitrogen atmosphere for 72 hours at thistemperature, after which 1 mL of the reaction product was used to treatthe glass bubbles as described in Example 1.

Synthesis of3-[4-(2-{(2-cyanoethyl)-[4-(6-nitro-benzothiazol-2-ylazo)-phenyl]-amino}-ethoxy)-phenyl]-propionicacid methyl ester

0.151 g (381 μmol)3-{(2-hydroxyethyl)-[4-(6-nitro-benzothiazol-2-ylazo)-phenyl]-amino}-propionitrile,64.4 mg (357 μmol) methyl 3-(4-hydroxyphenyl)-propionate and 0.117 g(446 μmol) triphenylphosphine were dissolved in 10 mL of tetrahydrofuran(THF) in a 50 mL flask at approximately 21° C. This solution was cooledto 0° C. by placing the flask in an ice/water bath. The flask wasequipped with an addition funnel containing a solution of 110 μL (559μmol) diisopropyl azodicarboxylate (DIAD) in 5 mL of THF. The DIAD/THFsolution was added dropwise to the stirred reaction mixture over aperiod of 2 hours under an atmosphere of nitrogen while the temperaturewas maintained at approximately 0° C. When the addition was complete,the reaction mixture was allowed to warm to approximately 21° C. Thereaction mixture was then stirred under an atmosphere of nitrogen for 20hours at approximately 21° C. The reaction mixture was condensed in arotary evaporator. The resulting material was partitioned between water(approximately 50 mL) and methylene chloride (CH₂Cl₂) (approximately 50mL). The organic layer was then removed, and the aqueous layer wasextracted twice more with CH₂Cl₂ (approximately 50 mL each time). Theorganic layers were combined, dried by passing through a bed ofanhydrous sodium sulfate, filtered, and condensed in a rotaryevaporator. The resulting solid was further purified by loading onto a 4by 32 cm silica gel column, then eluting with approximately 10:90 (byvolume) ethyl acetate:methylene chloride solution. Subsequent fractionscontaining the pure compound were combined, condensed under reducedpressure and then dried under vacuum of 0.3 mm mercury (40.0 Pa) atapproximately 21° C. to yield 73.7 mg of a solid subsequently confirmedby NMR spectroscopy to be3-[4-(2-{(2-cyanoethyl)-[4-(6-nitro-benzothiazol-2-ylazo)-phenyl]-amino}-ethoxy)-phenyl]-propionicacid methyl ester [¹H NMR (500 MHz, CDCl₃) δ 8.72 (d, J=2.4 Hz, 1H),8.29 (dd, J=2.4, 8.8 Hz, 1H), 8.12 (d, J=8.8 Hz, 1H), 8.00 (m, 2H), 7.11(m, 2H), 6.82 (m, 2H), 6.79 (m, 2H), 4.20 (t, J=5.0 Hz, 2H), 4.00 (t,J=5.0 Hz, 2H), 3.99 (t, J=7.1 Hz, 2H), 3.63 (s, 3H), 2.87 (t, J=7.6 Hz,2H), 2.81 (t, J=7.1 Hz, 2H), 2.57 (t, J=7.6 Hz, 2H)].

Synthesis of3-[4-(2-{(2-cyanoethyl)[4-(6-nitro-benzothiazol-2-ylazo)-phenyl]-amino}-ethoxy)-phenyl]-propionicacid

A 3.6 mg/mL lithium hydroxide (LiOH) in water solution was prepared bydissolving 71.9 mg of LiOH in 20 mL of deionized water. In a 20 mL vial,56.7 mg (102 μmol)3-[4-(2-{(2-cyanoethyl)-[4-(6-nitro-benzothiazol-2-ylazo)-phenyl]-amino}-ethoxy)-phenyl]-propionicacid methyl ester were dissolved in 4 mL of THF at approximately 21° C.1.09 mL of the aqueous LiOH solution was added to the vial containingthe methyl ester dye/THF solution. This vial was capped and the contentsmixed in a mechanical shaker, model “WRIST ACTION SHAKER MODEL 75” fromBurrell Scientific (Pittsburgh, Pa.) for 3 hours at approximately 21° C.The reaction mixture was condensed in a rotary evaporator. The resultingmaterial was partitioned between 0.1 N aqueous hydrogen chloride (HCl)(approximately 25 mL) and CH₂Cl₂ (approximately 25 mL). The organiclayer was then removed, and the aqueous layer was extracted twice morewith CH₂Cl₂ (approximately 25 mL each time). The organic layers werecombined, dried by passing through a bed of anhydrous sodium sulfate,filtered, and condensed in a rotary evaporator. The resulting solid wasdried under vacuum of 0.3 mm mercury (40.0 Pa) at approximately 21° C.to yield 48.7 mg of a solid subsequently confirmed by NMR spectroscopyto be3-[4-(2-{(2-cyanoethyl)-[4-(6-nitro-benzothiazol-2-ylazo)-phenyl]-amino}-ethoxy)-phenyl]-propionicacid [¹H NMR (500 MHz, d-6 acetone) δ 8.95 (d, J=2.5 Hz, 1H), 8.35 (dd,J=2.5, 8.8 Hz, 1H), 8.17 (d, J=8.8 Hz, 1H), 7.98 (m, 2H), 7.21 (m, 2H),7.17 (m, 2H), 6.88 (m, 2H), 4.32 (t, J=5.4 Hz, 2H), 4.16 (t, J=5.4 Hz,2H), 4.15 (t, J=7.1 Hz, 2H), 3.00 (t, J=7.1 Hz, 2H), 2.82 (t, J=7.6 Hz,2H), 2.54 (t, J=7.6 Hz, 2H)].

Example 1

0.9759 grams of glass bubbles, obtained under the trade designation“GLASS BUBBLES S15” from 3M Company (St. Paul, Minn.) were added to a100 mL round bottomed flask containing 20 mL deionized water, and thesuspension was stirred for 10 minutes at 21° C. The glass bubbles werethen isolated by vacuum filtration and washed with 10 mL of deionizedwater, followed by 50 mL of ethanol. 1 mL of[3-(triethoxysilyl)propyl]-carbamic acid2-{(2-cyanoethyl)-[4-(6-nitrobenzo-thiazol-2-ylazo)-phenyl]amino}ethylester was added to a 20 mL glass vial followed by 5 mL of a 95% byvolume aqueous ethanol solution and mixed in a mechanical shaker, model“WRIST ACTION SHAKER MODEL 75” from Burrell Scientific (Pittsburgh, Pa.)for 5 minutes at 21° C. The vial was removed from the shaker, the washedglass bubbles added, and the vial returned to the shaker for 2 hours.The resulting dyed glass bubbles were then isolated by vacuumfiltration, washed with 50 mL ethanol followed by sufficient acetoneuntil the eluent was essentially colorless. The resulting pink glassbubbles were allowed to air dry at 21° C. for 18 hours. 0.30 grams ofthe dyed glass bubbles were uniformly mixed into 10.0 grams of a whiteautomotive body filler that had been dispensed from the cartridge of abody filler kit, obtained under the trade designation “3M PREMIUM BODYFILLER, PART No. 50597” from 3M Company. The resulting body filler waspink. 0.21 grams of a white 50% benzoyl peroxide hardener paste,obtained under the trade designation “BENOX B-50” from SyrgisPerformance Initiators, Inc. (Helena, Ark.) was then uniformly mixed ona palette for 45 seconds at 21° C. with the pink body filler. After 12minutes, a hardened white body filler was obtained with no residual pinkcolor.

Example 2

A 2.1 mg/mL solution of3-[4-(2-{(2-cyanoethyl)-[4-(6-nitro-benzothiazol-2-ylazo)-phenyl]-amino}-ethoxy)-phenyl]-propionicacid in acetone was prepared by dissolving 8.2 mg of3-[4-(2-{(2cyanoethyl)-[4-(6-nitro-benzothiazol-2-ylazo)-phenyl]-amino}-ethoxy)-phenyl]-propionicacid in 4.0 mL of acetone. 0.3020 grams of ultrafine uncoated calciumcarbonate, obtained under the trade designation “SOCAL 31” from SolvayChemicals, Inc. (Brussels, Belgium), were added to a 20 mL vialcontaining a solution prepared by adding 300 μL of the 2.1 mg/mLsolution of3-[4-(2-{(2-cyanoethyl)-[4-(6-nitro-benzothiazol-2-ylazo)-phenyl]-amino}-ethoxy)-phenyl]-propionicacid in acetone to 1.7 mL of acetone. The vial was capped and thecontents mixed in a mechanical shaker, model “WRIST ACTION SHAKER MODEL75” from Burrell Scientific (Pittsburgh, Pa.) for 2 hours atapproximately 21° C. The resulting dyed calcium carbonate was isolatedby vacuum filtration and washed with sufficient acetone until the eluentwas essentially colorless. The resulting pinkish-purple calciumcarbonate powder was dried under vacuum of 0.3 mm mercury (40.0 Pa) atapproximately 70° C. for 2 hours. 39.6 mg of the dyed calcium carbonatepowder were uniformly mixed into 5.15 grams of a white automotive bodyfiller that had been dispensed from the cartridge of a body filler kit,obtained under the trade designation “3M PREMIUM BODY FILLER, PART No.50597” from 3M Company. The resulting body filler was pink. 0.120 gramsof a white 50% benzoyl peroxide hardener paste, obtained under the tradedesignation ‘BENOX B-50” from Syrgis Performance Initiators, Inc.(Helena, Ark.) was then uniformly mixed on a palette for 60 seconds at21° C. with the pink body filler. After 12 minutes, a hardened whitebody filler was obtained with no residual pink color.

Example 3

A 2.1 mg/mL solution of3-[4-(2-{(2-cyanoethyl)-[4-(6-nitro-benzothiazol-2-ylazo)-phenyl]-amino}-ethoxy)-phenyl]-propionicacid in acetone was prepared by dissolving 8.2 mg of3-[4-(2-{(2-cyanoethyl)-[4-(6-nitro-benzothiazol-2-ylazo)-phenyl]-amino}-ethoxy)-phenyl]-propionicacid in 4.0 mL of acetone. 0.2997 grams of granular sodium metaboratehydrate, obtained from Sigma-Aldrich, Company (St. Louis, Mo.), wereadded to a 20 mL vial containing a solution prepared by adding 600 μL ofthe 2.1 mg/mL solution of3-[4-(2-{(2-cyanoethyl)-[4-(6-nitro-benzothiazol-2-ylazo)-phenyl]-amino}-ethoxy)-phenyl]-propionicacid in acetone to 1.4 mL of acetone. The vial was capped and thecontents mixed in a mechanical shaker, model “WRIST ACTION SHAKER MODEL75” from Burrell Scientific (Pittsburgh, Pa.) for 2 hours atapproximately 21° C. The resulting dyed sodium metaborate was isolatedby vacuum filtration and washed with sufficient acetone until the eluentwas essentially colorless. The resulting pinkish-purple sodiummetaborate granules were dried under vacuum of 0.3 mm mercury (40.0 Pa)at approximately 70° C. for 2 hours. A mortar and pestle were used togrind the dyed sodium metaborate granules into a fine powder. 21.7 mg ofthe dyed sodium metaborate powder were uniformly mixed into 5.01 gramsof a white automotive body filler that had been dispensed from thecartridge of a body filler kit, obtained under the trade designation “3MPREMIUM BODY FILLER, PART No. 50597” from 3M Company. The resulting bodyfiller was pink. 0.125 grams of a white 50% benzoyl peroxide hardenerpaste, obtained under the trade designation ‘BENOX B-50” from SyrgisPerformance Initiators, Inc. (Helena, Ark.) were then uniformly mixed ona palette for 60 seconds at 21° C. with the pink body filler. After 12minutes, a hardened white body filler was obtained with no residual pinkcolor.

Various modifications and alterations of this disclosure may be made bythose skilled in the art without departing from the scope and spirit ofthe disclosure, and it should be understood that this invention is notto be unduly limited to the illustrative embodiments set forth herein.

What is claimed is:
 1. A treated filler comprising: an inorganic fillerhaving on at least a portion of its surface a compound of formula

wherein R is hydrogen or alkyl; X is alkylene, arylalkylene, oralkylarylene, wherein alkylene, arylalkylene, and alkylarylene areoptionally interrupted by at least one of an ether, thioether, amine,amide, ester, thioester, carbonate, thiocarbonate, carbamate,thiocarbamate, urea, or thiourea, and wherein alkylene is optionallyinterrupted by arylene; W is hydroxyl, a sulfonic acid group, aphosphonic acid group, a carboxylic acid group, —NHR¹, epoxy, or—Si(Y)_(x)(Z¹)_(3-x); R¹ is hydrogen, alkyl, aryl, arylalkylenyl, oralkylarylenyl; Y is alkyl, aryl, arylalkylenyl, or alkylarylenyl; eachZ¹ is independently halide, hydroxyl, alkoxy, aryloxy, acyloxy,polyalkyleneoxy, —O— covalently bonded to the surface of the filler, or—O— bonded to another silicon atom to form a siloxane, wherein alkoxyand acyloxy are optionally substituted by halogen, and wherein aryloxyis optionally substituted by halogen, alkyl, or haloalkyl; and x is 0 or1, and wherein the compound is at least one of covalently bonded orionically bonded to the inorganic filler.
 2. The treated filler of claim1, wherein the inorganic filler comprises at least one of alumina, tinoxides, antimony oxides, silica, zirconia, titania, glass, ceramics,calcium carbonate, or sodium metaborate.
 3. The treated filler of claim1, wherein the inorganic filler comprises at least one of calciumcarbonate, sodium metaborate, or hollow glass elements.
 4. The treatedfiller of claim 1, wherein W is a carboxylic acid group or—Si(Y)_(x)(Z¹)_(3-x), wherein x is 0, and wherein each Z¹ isindependently hydroxyl, alkoxy, —O— covalently bonded to the surface ofthe filler, or —O— bonded to another silicon atom to form a siloxane. 5.The treated filler of claim 1, wherein W is a sulfonic acid group, aphosphonic acid group, or a carboxylic acid group.
 6. The treated fillerof claim 1, wherein X is alkylene that is optionally interrupted by atleast one ether, ester, carbonate, carbamate, or arylene.
 7. The treatedfiller of claim 1, wherein R is H.
 8. A composition comprising a curablepolymeric resin and the treated filler of claim
 1. 9. The composition ofclaim 8, further comprising a free radical initiator.
 10. Thecomposition of claim 9, wherein the free-radical initiator is an organicperoxide.
 11. The composition of claim 8, wherein the curable polymericresin is an unsaturated polyester resin.
 12. The composition or methodof claim 8, wherein the composition further comprises at least one ofstyrene monomer, a substituted styrene monomer, an acrylate monomer, ora methacrylate monomer.
 13. A method for determining degree of cure of acurable polymeric resin, the method comprising: providing a compositioncomprising a curable polymeric resin, a free-radical initiator, and thetreated filler of claim 1 in an amount sufficient to provide thecomposition with a first absorbance at a wavelength in a range from 400nanometers to 700 nanometers; and allowing the composition to cure toprovide a cured composition, wherein the cured composition has a secondabsorbance at the wavelength that is different from the firstabsorbance.
 14. A method of making the treated filler of claim 1, themethod comprising treating the inorganic filler with the compoundrepresented by formula:

wherein R is hydrogen or alkyl; X is alkylene, arylalkylene, oralkylarylene, wherein alkylene, arylalkylene, and alkylarylene areoptionally interrupted by at least one of an ether, thioether, amine,amide, ester, thioester, carbonate, thiocarbonate, carbamate,thiocarbamate, urea, or thiourea, and wherein alkylene is optionallyinterrupted by arylene; W is hydroxyl, a sulfonic acid group, aphosphonic acid group, a carboxylic acid group, —NHR¹, epoxy, or—Si(Y)_(x)(Z¹)_(3-x); R^(i) is hydrogen, alkyl, aryl, arylalkylenyl, oralkylarylenyl; Y is alkyl, aryl, arylalkylenyl, or alkylarylenyl; eachZ¹ is independently halide, hydroxyl, alkoxy, aryloxy, acyloxy,polyalkyleneoxy, —O— covalently bonded to the surface of the filler, or—O— bonded to another silicon atom to form a siloxane, wherein alkoxyand acyloxy are optionally substituted by halogen, and wherein aryloxyis optionally substituted by halogen, alkyl, or haloalkyl; and x is 0or
 1. 15. The method of claim 14, wherein the inorganic filler comprisesat least one of alumina, tin oxides, antimony oxides, silica, zirconia,titania, glass, ceramics, calcium carbonate, or sodium metaborate. 16.The method of claim 14, wherein the inorganic filler comprises at leastone of calcium carbonate, sodium metaborate, or hollow glass elements.17. The method of claim 14, wherein W is a carboxylic acid group or—Si(Y)_(x)(Z¹)_(3-x), wherein x is 0, and wherein each Z¹ isindependently hydroxyl, alkoxy, —O— covalently bonded to the surface ofthe filler, or —O— bonded to another silicon atom to form a siloxane.18. The method of claim 14, wherein W is a sulfonic acid group, aphosphonic acid group, or a carboxylic acid group.
 19. The method ofclaim 14, wherein W is a carboxylic acid group or —Si(Y)_(x)(Z¹)_(3-x),wherein x is 0, and wherein each Z¹ is alkoxy.